<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        // 接收用户输入的用户名和密码，若用户名为"admin"，密码为"123456"，则提示用户登录成功！否则，让用户一直输入。
        var user = prompt('请输入用户名:');
        var password = prompt('请输入密码:');
        while (user != 'admin' || password != '123456') {
            var user = prompt('请输入用户名:');
            var password = prompt('请输入密码:');
        }
        alert('登陆成功');
    </script>
</head>

<body>

</body>

</html>